A diamond semiconductor is a wide bandgap semiconductor having a large band gap energy of 5.5 eV. The diamond semiconductor is strong and has excellent material properties such as a high carrier mobility (electron: 4500 cm2/V·sec, hole: 3800 cm2/V·sec) and a high breakdown field strength (10 MV/cm) as well as a high thermal conductivity (20 W/cm·K). Therefore, the diamond semiconductors have excellent characteristics as a material for a semiconductor device having ultra-high breakdown voltage/ultra-high efficiency.
So far, power devices using diamond semiconductors have been actively developed.